Oil well jar



C. M. HOWARD OIL WELL JAR Feb. 12, 1952 Filed Feb. 27, 1951 Jim/Mix Patented Feb. 12, 1952 UNITED STATES PATENT OFFICE 2,585,318

' oIL WELL JAR Clifford M. Howard, Fontana, Calif.

Application February .27, 1951, Serial No. 212,977

a This inventionrelates to an oil well jar of the longitudinally striking type, that is, one in which a longitudinal movement is imparted to the tool causing-a -latch-means to be released and permit ting a hammer tostrike against an anvil, thus Striking a blow against the body of the tool which is attached to the lost or stuck pipe.

An object of my invention is to provide a novel oil well jar in which a collet is employed to engage a tapered shoulder, the collet compressing under tension to permit the mandrel to release and cause the hammer to strike the anvil.

Another object of my invention is to provide a novel means of eliminating the back-lash in the tool due to a required looseness inthe spline construction of the tool.

Still another object of my invention is to provide a novel means of wedging the collet against its shoulder by means of a spring pressed wedge ring, the tension of the spring being variable to vary the longitudinal pull necessary to operate the tool.

A feature of my invention is to provide a novel finger ring constructionin which tapered fingers are wedged into the spline construction of the tool-to eliminate back-lash.

Other objects, advantages and features of invention may appear from the accompanying drawing, the subjoined detailed description and the appended claims.

In the drawing:

Figure 1 is a partial longitudinal sectional view of my tool in collapsed position.

Figure 2 is a partial longitudinal sectional view of my tool in extended position.

Figure 3 is a sectional view taken on line 3-3 of Figure 1.

Figure 4 is a sectional view taken on line 4-4 of Figure 1.

Figure 5 is a fragmentary longitudinal sectional view showing the finger ringand collet construction.

Referring more particularly to the drawing, the numeral I indicates a tubular body which may be formed in two parts 23, which are threaded together as shown at 4. A mandrel '5 extends into the body and is longitudinally movable within the body, as will be further described. A packing nut 5 screws into the top of the body I and compresses the packing 7 around the mandrel 5 to prevent fluid leakage.

An anvilring or nut 8 is threaded into'the upper part of the portion 2 of the body and is arranged below the packing l, substantially as shown. This anvil projects inwardly a slight dis--v 9 Claims. (0]. 255-27) 2 tance, as shown, so as to provide a shoulder against which themandrel'shoulder 9 strikes. A coupling IE] on the upper end of. the 'mandrel permits this mandrel to be threaded on to the drill pipe upon which the tool is run.. The lower;

part 3 of the body I is formed with a threaded- Whatever the jar might be run on. The lower end of the mandrel 5 is formed with a plurality of spaced vertical slots I2 into whichthe spines i3 on the body I extend. In order that the mandrel 5 may drop freely, it is necessary that splines [3 will fit rather loosely in the slots l2 of the mandrel. This would normally cause a certain amount of looseness or back-lash and I overcome this looseness in the following manner: A finger ring I4 is mounted in the lowerpor tion 3 of the body I, as best shown in Figure 5. The finger ring 14 includes a base l5 from which. springs l6 extend to engage the ring I4 and press this ring upwardly. The lower end of the finger I! of the mandrel 5 is tapered, as shown at I8; and the tapered fingers It fit against the taper l8 on the one side. and against the splines IS on .the other, thus wedging between the splines and the fingers H, which takes out the loosenessv or.play. between the splines l3 and the fingers l7, thereby. eliminating back-lash. I The base l5 rests on. a shoulder l9 in its lower. position andv the ring is prevented from moving upwardly by the pins 20 which project .horizofntally from the fingers M and engage the lower edge of the splines l3, thus eliminating the .up ward movement of the finger ring. A collet 2| is tubular in form and is cut length:

Wise to form spring fingers, substantially as' shown. The upper end of the collet screws into the lower end of the mandrel 5, as shown at 22,. Its lower end is provided with tapered shoulders 23 which engage the. lower tapereduedgeof 8,, ring 24 in-the body portion 3. Thecollet 21, is spread outwardly to engage the ring 24 by means of a wedge ring 25 which is pressed upwardly by the coil spring 26. The spring 26 restson a nut Z'i which screws into the body portion 3 adjacent its lower end and can be threaded up: wardly or downwardly to vary the tension'of the spring 26,.as may be necessary. The spring 26 presses the wedge ring 25 upwardly with' varying pressure, thus expanding the collet 2i and causing the tapered shoulders 23 to press against the ring 24 so that a considerable force is required before the mandrel 5 can be pulled upwardly in the body 1. When the collet 2| escapes the ring 24 it will move upwardly permitting the hammer 9 to strike the anvil 8 and causing an upward jar or blow on the body I.

Normally, the oil Well jar is held in collapsed position by the shear pins 28 and this collapsed position is maintained during normal drilling operations. In the collapsed position the finger ring I4 is in the position shown in Figure 5 and backlash is taken out of the tool. When it is desired to jar to remove drill pipe which might be stuck or other tool attached to the jar, then the shear pins 28 are sheared and the tool is used as a longitudinally striking jar.

Having described my invention, I claim:

1. An oil well jar comprising a tubular body, coupling means on the lower end of said body, a mandrel extending into said body and slidable vertically therein, coupling means on the upper end of said mandrel, a shoulder in said body forming an anvil, a second shoulder on the mandrel forming a hammer and engageable with the anvil, a latch ring in said body, releasable means on the mandrel engaging said latch ring, splines on the inside of said body, said mandrel having grooves therein to receive the splines, said grooves forming fingers therebetween in the mandrel, a finger ring mounted in said body, projecting fingers on said finger ring, said projecting fingers engaging the first named fingers to take up looseness between the first named fingers and the splines.

2. An oil well jar comprising a tubular body, coupling means on the lower end of said body, a mandrel extending into said body and slidable vertically therein, coupling means on the upper end of saidmandrel, a shoulder in said body forming an anvil, a second shoulder on the mandrel forming a hammer and engageable with the anvil, a latch ring in said body, releasable means on the mandrel engaging said latch ring, splines on the inside of said body, said mandrel having grooves therein to receive the splines, said grooves forming fingers therebetween in the mandrel, a finger ring mounted in said body, projecting fingers on said finger ring, said projecting fingers engaging the first named fingers to take up looseness between the first named fingers and the splines, and spring means pressing the finger ring into engagement with the first named fingers.

3. An oil well jar comprising a tubular body, coupling means on the lower end of said body, a mandrel extending into said body and slidable vertically therein, coupling means on the upper end of said mandrel, a shoulder in said body forming an anvil, asecond shoulder on the man drel forming a hammer and engageable with the anvil, a latch ring in said body, releasable means on the mandrel engaging said latch ring, splines on the inside of said body, said mandrel having grooves therein to receive the splines, said grooves forming fingers therebetween in the mandrel, a finger ring mounted in said body, projecting fingers on said finger ring, said projecting fingers engaging the first named fingers to take up looseness between the first named fingers and the splines, and spring means pressing the finger ring into engagement with the first named fingers, a shoulder in the body on which the finger ring rests, and pins projecting from the last named fingers and engageable with said splines to eliminate upward movement of the finger ring.

4.An oil well jar comprising a tubular body, coupling means on the lower end of said body, a mandrel extending into said body and slidable vertically therein, coupling means on the upper end of said mandrel, a shoulder in said body forming an anvil, a second shoulder on the mandrel forming a hammer and engageable with the anvil, a collet depending from said mandrel, a shoulder on the inside of the body engageable by said collet, said collet being releasable from said shoulder on upward movement of the mandrel, splines on the inside of said body, said mandrel having grooves therein to receive the splines, said grooves forming fingers therebetween in the mandrel, a finger ring mounted in said body. projecting fingers on said finger ring, said projecting fingers engaging the first named fingers to take up looseness between the first named fingers and the splines.

5.An oil well jar comprising a tubular body, coupling means on the lower end of said body, a mandrel extending. into said body and slidable vertically therein, coupling means on the upper end of said mandrel, a shoulder in said body forming an anvil, a second shoulder on the mandrel forming a hammer and engageable with the anvil, a collet depending from said mandrel, a shoulder on the inside of the body engageable by said collet, said collet being releasable from said shoulder on upward movement of the mandrel, a wedge ring engageable with the collet, and spring means pressing said wedge ring upwardly against the bottom of the collet, splines on the inside of said body, said mandrel having grooves therein to receive the splines, said grooves forming fingers therebetween in the mandrel, a finger ring mounted in said body, projecting fingers on said finger ring, said projecting fingers engaging the first named fingers to take up looseness between the first named fingers and the splines.

6. An oil well jar comprising a tubular body, coupling means on the lower end of said body, a, mandrel extending to said body and slidable vertically therein, coupling means on the upper end of said mandrel, a shoulder on the inside of the body forming an anvil, a second shoulder on the mandrel forming a hammer, said hammer being engageable with the anvil, splines on the inside of the body, said mandrel having vertical slots therein to receive the splines, said slots forming fingers in the mandrel therebetween, the lower ends of said fingers being tapered, a finger ring mounted in the body below the mandrel, upwardly projecting fingers on the finger ring, the last named fingers engaging the tapered faces of the first named fingers, and the splines to prevent back-lash in the mandrel, a collet depending from the mandrel, a latch shoulder in the body engageable by the collet, said collet being releasable from the last named shoulder on upward pull of the mandrel.

7. An oil well jar comprising a tubular body, coupling means on the lower end of said body, a mandrel extending to said body and slidable vertically therein, coupling means on the upper end of said mandrel, a shoulder on the inside of the body forming an anvil, a second shoulder on the mandrel forming a hammer, said hammer being engageable with the anvil, splines on the inside of the body, said mandrel having vertical slots therein to receive the splines, said slots forming fingers in the mandrel therebetween, the lower ends of said fingers being tapered, a finger ring mounted in the body below the mandrel, upwardly projecting fingers on the finger ring, the last named fingers engaging the tapered faces of the first named fingers and the splines to prevent back-lash in the mandrel, a collet depending from the mandrel, a latch shoulder in the body engageable by the collet, said collet being releasable from the last named shoulder on upward pull of the mandrel, a wedge ring engaging the lower end of the collet and spreading the collet into the last named shoulder, and spring means pressing the wedge ring against the collet.

8. An oil well jar comprising a tubular body, coupling means on the lower end of said body, a mandrel extending into said body and slidable vertically therein, coupling means on the upper end of said mandrel, a shoulder on the inside of the body forming an anvil, a second shoulder on the mandrel forming a hammer, said hammer being engageable with the anvil, splines on the inside of the body, said mandrel having vertical slots therein to receive the splines, said slots forming fingers in the mandrel therebetween, the lower ends of said fingers being tapered, a finger ring mounted in the body below the mandrel, upwardly projecting fingers on the finger ring, the last named fingers engaging the tapered faces of the first named fingers and the splines to prevent back-lash in the mandrel, spring means engaging the finger ring and pressing said finger ring into engagement with said fingers on the mandrel, a collet depending from the mandrel, a latch shoulder in the body engageable by the collet, said collet being releasable from the last named shoulder on upward pull of the mandrel.

9. An oil well jar comprising a tubular body, coupling means on the lower end of said body, a mandrel extending into said body and slidable vertically therein, coupling means on the upper end of said mandrel, a shoulder on the inside of: the body forming an anvil, a second shoulder on the mandrel forming a hammer, said hammer being engageable with the anvil, splines on the inside of the body, said mandrel having vertical slots therein to receive the splines, said slots forming fingers in the mandrel therebetween, the l0wer ends of said fingers being tapered, a finger ring mounted in the body below the mandrel, upwardly projecting fingers on the finger ring, the last named fingers engaging the tapered faces of the first named fingers and the splines to prevent back-lash in the mandrel, spring means engaging the finger ring and pressing said finger ring into engagement with said fingers on the mandrel, a collet depending from the mandrel, a latch shoulder in the body engageable by the collet, said collet being releasable from the last named shoulder on upward pull of the mandrel, a wedge ring engaging the lower end of the collet and spreading the collet into the last named shoulder and spring means pressing the wedge ring against the collet.

CLIFFORD M. HOWARD.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,977,110 Burns et al Oct. 16, 1934 2,121,267 Shaffer June 21, 1938 

